Prophylactic percutaneous left ventricular assist device in pregnancy

Short abstract

Pregnancy-associated cardiomyopathy can present earlier in gestation than traditionally defined peripartum cardiomyopathy. Management and optimal delivery timing for these patients are not well defined. We present the case of a 30-year-old primigravid at 26 weeks who presented with new onset ventricular tachycardia, biventricular cardiac failure, and severe mitral regurgitation. She was medically stabilized for two weeks prior to delivery with modest improvement in her condition. Due to concern for life-threatening cardiac failure and pulmonary edema at the time of delivery, a percutaneous left ventricular assist device was inserted immediately prior to cesarean delivery. She remained on mechanical circulatory support for 36 h. We discuss considerations regarding use of a percutaneous left ventricular assist device as a novel therapy to support the hemodynamic changes following delivery in parturients with decompensated heart failure.

Introduction

Peripartum cardiomyopathy complicates 1/1000 to 1/4000 live births in the United States.¹ Although uncommon, cardiomyopathy during pregnancy was the cause of 11% of maternal deaths in the United States from 2011 to 2013.² Although patients with cardiomyopathy characteristically present after 32 weeks’ gestation or within one month postpartum, a minority present prior to 32 weeks. Elkayam et al. evaluated patients presenting at earlier gestational ages, noting similar clinical profiles and maternal outcomes to those with more classic presentations, thus suggesting the term pregnancy-associated cardiomyopathy may be more appropriate.³

Use of mechanical assist devices has been reported in pregnancy-associated cardiomyopathy, although this has mostly been limited to the intra-aortic balloon pump, thoracic biventricular assist devices, and the total artificial heart.⁴ Following patient consent, we present a case detailing novel use of a percutaneous left ventricular assist device as a prophylactic means to prevent peripartum cardiogenic shock.

Case

A 30-year-old primigravid woman at 26 1/7 weeks’ gestation presented to Labor & Delivery with complaints of several weeks of dyspnea, chest pain, and palpitations, worsening over the past three days. Her medical history was unremarkable. Her vital signs included blood pressure of 100/88, oxygen saturation of 97–100%, tachycardia of 106 to 279 beats/min, and tachypnea of 30 breaths/min. Electrocardiogram identified non-sustained ventricular tachycardia and multifocal premature ventricular contractions. Echocardiography showed a left ventricular ejection fraction of 15–20% with severe left atrial dilation and severe mitral regurgitation. Brain natriuretic peptide was 1380 pg/mL. Fetal growth was appropriate and fetal monitoring showed a category I tracing.

She was admitted to the medical intensive care unit, where beta-adrenergic blockade (intravenous esmolol), intravenous lidocaine, therapeutic anticoagulation, and furosemide were initiated. Antenatal corticosteroids were administered for fetal lung maturity.

On hospital days 2–3, the patient mildly symptomatically improved (albeit remained NYHA class IV) and with less frequent arrhythmias; however, repeat echocardiography showed no significant improvement in function. Attempts to wean the lidocaine were unsuccessful and she continued to experience shortness of breath and orthopnea.

Following multidisciplinary discussion, delivery was offered to the patient early in her course; however, she desired short-term expectant management. The goal of 28 weeks’ gestation was targeted to balance improved neonatal outcome and maternal risks due to sustained tachyarrhythmia and increasing cardiovascular burden of her advancing gestation.

Delivery of the fetus was planned for hospital day 13 at 27 6/7 weeks’ gestation. She was aggressively diuresed with furosemide in anticipation of delivery and received rescue betamethasone and magnesium sulfate for fetal benefit. A Swan-Ganz catheter and an arterial line were placed the night prior to delivery.

Immediately prior to delivery, she underwent percutaneous left ventricular assist device placement (Impella CP; Abiomed, Danvers, MA) through femoral vascular access under sedation and local anesthesia. Pulse-dose unfractionated heparin was given during the procedure. She subsequently underwent general anesthesia and a cesarean delivery was performed. Her 1025 g female infant was transferred to the neonatal intensive care unit with apgars of 6 and 8. The patient remained intubated and was transferred to the surgical intensive care unit, where she was extubated the same day. The ventricular assist device was initially on maximal settings with a flow rate of 3.5 l/min, but was titrated down following aggressive diuresis and ultimately removed 36 h following delivery. Anticoagulation was restarted at a subtherapeutic dose 6 h following delivery and increased to a full therapeutic dose 24h following delivery. Her shortness of breath and orthopnea improved immediately postoperatively.

Cardiac magnetic resonance imaging obtained during her post-operative course showed thinning and akinesis of the basal and mid-level wall of the left ventricle with associated patchy and transmural late gadolinium enhancement. She showed modest clinical improvement and was discharged on post-operative day 9 on a regimen of mexiletine, metoprolol, enalapril, furosemide, spironolactone, warfarin, and a wearable cardioverter defibrillator. She was counseled against pursuing a subsequent pregnancy due to the high risk of mortality and initially desired placement of a levonorgestrel intrauterine device but has not presented for insertion.

At one month post-delivery, she continued to have dyspnea on exertion after ambulating one block. Repeat echocardiography showed unchanged left cardiac function with an ejection fraction of 20%; however, right-sided cardiac function was recovered. She has been recommended to undergo placement of an implantable cardioverter defibrillator.

Discussion

In parturients with decompensated heart failure, the greatest risk for death is in the immediate postpartum period due to rapid autotransfusion of blood volume into the maternal circulation. This case represents the first known use of a percutaneous left ventricular assist device to support maternal cardiac output at the time of delivery. Previous use has been described in the postpartum setting 12 h following cesarean delivery in an acutely decompensating patient.⁵ The device implanted in this case is approved for temporary left ventricular support (≤4–6 days) for patients in cardiogenic shock not responsive to optimal medical management and conventional treatment measures as well as for prophylactic use during high-risk percutaneous coronary interventions. It functions to augment cardiac output up to 2.5–5 l/min independent of the patient’s cardiac pump strength by delivering blood from the left ventricle to the ascending aorta.⁶

Therapeutic anticoagulation is necessary with a percutaneous left ventricular assist device due to the high risk of thromboembolism. The implant in this case is known to cause hemolysis, and the effect to the fetus with the device in situ is unknown. Our team considered placing the device 24 h pre-operatively to optimize her hemodynamics further; however, given the uncertainty of the effect to the fetus, the decision was made to proceed with placement immediately prior to delivery.

As with many patients presenting with pregnancy-associated cardiomyopathy, our patient was previously healthy and did not have any baseline imaging of her heart. The results of her cardiac magnetic resonance imaging are potentially more consistent with a chronic process, although late gadolinium enhancement is a non-specific finding that can also be associated with pregnancy-associated cardiomyopathy.⁷ She has been referred for genetic testing and follow-up with our heart failure cardiology team.

Prophylactic use of a percutaneous left ventricular assist device at the time of cesarean delivery in a patient with pregnancy-associated cardiomyopathy has not been previously described. Consideration should be given to the ability of the device to support cardiac output and prevent the sequelae of cardiogenic shock following the hemodynamic changes associated with delivery.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Ethical approval

Written and verbal consent has been obtained from the patient whose care is described in this case report.

Guarantor

JMW.

Contributorship

All listed authors made a substantial contribution to the care of this patient, assisted with drafting the article, and approved the version to be published.